At this point, I would like to delete and SSH keys on my machine and basically start fresh. If anyone has insight on how these massive files were formed please let me know, and if there are any tips on how to make sure this doesn’t happen are greatly appreciated.

Git is a version control system. It allows you to control the changes on your files by making snapshots of how all your files (and then only changed files) look at the moment of the commit. You can read more how this awesome tool works here.

The problem is you have initialized or cloned a git repo on your home folder and git probably made a snapshot of all your files. You can safely rm -rf ~/.git to get rid of the repo.

Edit: Maybe you'll want to erase the code that was in the repo too. Next time you initiate a git repo, do it in a separate/isolated folder.